Cable telegraphy.



I. KITSEE.

CABLE TELEGRAPHY.

APPLICATION FILED MT. 2a, 1908.

h i 9 9 WITNESSES: ll- IN VENTOR. I $M N COLUMBIA PLANOGRAFHCO..WA5HINGTON, D. c.

Patented May 5, 1914.

UNITED STATES PATEN FIQ.

ISIDOR- KITSEE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR, BY MESNEASSIGN- MENTS,.TO AMERICAN TELEPHONE AND TELEGRAPH COMPANY, OF NEW YORK,

N. Y., A CORPORATION OF NEW YORK.

CABLE TELEGRAPHY.

Specification of Letters Patent.

Patented May 5, 1914.

Application filed October 28, 1908. Serial No. 459,963.

'rnia-kes the cmplcyn'ient of electro-magnetic again give rise to anunstable electrical state,

sion.

for the reason that it is impossible to arrange matters so as to alwayscharge and discharge the condensers in rhythmic succes- The differentcharging of these con dcnsers reacts with different degrees on any ofthe receiving devices and this gives rise to the well-known moving ofthe zero.

In the course of my experiments, covering a period of years, I havetried to reduce the cable, electrically speaking, to the state of a landline. in which nothing else but the resistance of the conductor needs tobe taken into consideration. After experimenting with relays ofdifferent. construction I had recourse to an arrangement whereby thereceiving end is connected to one coil of a transformer and thendirectly grounded; the second coil of the transformer being locallyconnected to a translating organism. I discarded all condensers andconnected the cable at thetransmitting end directly to source of currentwith the aid of which reversals may be transmitted I tried transformersof different ratios. The best result obtained by me was with atransformer with closed ma netic circuit; the coil inserted in the cablehaving a value of about 30,000 ohms and the coil locally to be connectedto the translating devices having a value of about 780 ohms.

In some of my tests, a galvanometer inserted directly in the cableshowed a deflection of over degrees, fluctuating from the right to left,nothing else being in the cable and the cable being grounded without theinterposition of any battery, thus showing that the current waves alwayspresent in the cable are in themselves sufficient to actuate a receivingdevice, notably as delicate an instrument as is required in cabletelegraphy.

When I placed the coil of higher value in the cable and connected thegalvanometer locally to the coil of lower value, the galvanometer stillfluctuated, but did not show more than from one-half to two deflections.

Placing in the circuit of the coil of lower value in series with thegalvanometer a condenser of three inicrofarads, the fluctuation ceasedentirely. An increase of this capacity to fifty microfarads again gaverise to a slight fluctuation of the needle' It has to be stated thatsome of these experiments were made on a cable running from Canso, N.8., to New York, N. Y.. a distance of over 900 miles. In receivingimpulses from Canso, it was found that these impulses could not beutilized for the operation of a receiving device if only threemicrofarads are inserted in the transformer circuit. But when thecondenser capacity was raised to about five inicrofarads, the im pulsesreceived from Canso were strong enough for all purposes. In one of theex periments, the coil of lower value was inserted in the cable and thecoil. of higher value connected locally to a condenser with thereceiving device; the electro-motive force of the transmitted currentbeing, as usual, Ql:.V()ltS. The receiver a siphon recorder) did notanswer. After repeated trials with step-up as well as step-down tranformers, I came to the conclusion that for practical working a step-downtransformer is required to produce good results and that it is best toplace in the local circuit an adjustable condenser adapted to be variedin accordance with requirements.

Coming now to the detailof the arrangement, reference is taken to theaccompanying drawing which illustrates in diagrammatic view a cablesystem embodying my. invention.

In this drawing; 1, 1, are the two parts of. the cable proper; 2 is thetransmitting two sets of batteries i and 5 placed in series as to theline and in opposition as to each other; the source 5 of higherelectromotive force than the source l. The source 5 is here grounded at6 with the interposition of the resistance 7. T o the junction of thesources el and 5 is connected the lever of the key 8 grounded also at 6.The operation of this part of the system is as follows z Normally, acurrent will flow from 5 in the direction of the unfeathered arrow overthe cable. \Vhen the key is closed, the source 5 is short circuited andthe current from l will flow in the direction of the feathered arrowover the cable and this reversal of the current will actuate thetransformer at the receiving station. At the receiving station 3, 9 isthe transformer as an entirety, of which 10 is the coil inserted in thecable and 11 the coil connected locally to the translating organism.

As stated above, I have found that it is best to use a step-downtransformer and the ratio of about to l was found by me to give the bestresult; this, for the reason that the incoming impulses are only ofminute quantity and the quantity has to be increased, the receivingdevice allowing a decrease in the electro-niotive force.

12 is a variable condenser and 13 is the translating device, here shownas an electromagnetic relay; the armature and one forward stop of sameconnected to the local circuit 14.. In this local circuit the necessarydevices to receive the message by sound, record, or print, can beplaced.

Having now described my invention, What I claim as new and desire tosecure by Letters Patent is A system of cable telegraphy comprising forthe transi'nitting station two sources of current connected in the lineof transmission, but in opposition as to each other; a resistance forone of said sources and a ground connecting one pole of said source withthe interposition of said resistance to said ground; a transmitting key;one part of said transi'nitting key connected to the junction of saidtwo sources; the other part of said transmitting key grounded; andcomprising for the receiving station a transformer; one-coil connectedto the cable and ground, respectively; the second coil connected to alocal circuit; a condenser for said local circuit, an. electromagneticreceiver for said local circuit and a local circuit for saidelectro-magnetic receiver.

in testimony whereof I {tlfiX my signature in presence of two witnesses.

ISTDOR KITSEE.

Witnesses EDITH R. STILLEY, Haiti 0. SMITH.

Copies of this patent may be obtained for live cents each, by addressingthe Commissioner of Patents, Washington, D. G.

